Question

我使用的是SQL Server 2005 SP3标准版，但无法创建索引视图（尝试在MeasurementDataID上创建聚簇索引）。我知道标准版不会在查询中使用索引视图，除非使用了noexpand查询提示。

错误消息 - 因为视图引用了一个未知值和可以为空的表达式的聚合

另外，为什么我需要count_big（*）??

CREATE VIEW [CPSync].[vwGetColorChars] WITH SCHEMABINDING
AS
    SELECT MC.MeasurementDataID
       , SUM(CASE WHEN CC.ColorCharID = 11 THEN [ColorCharsValue] END ) AS [Gray_a*] 
       , SUM(CASE WHEN CC.ColorCharID = 12 THEN [ColorCharsValue] END) AS [Gray_b*]
       , SUM(CASE WHEN CC.ColorCharID = 4 THEN [ColorCharsValue] END) AS [ΔF]
       , SUM(CASE WHEN CC.ColorCharID = 9 THEN [ColorCharsValue] END) As DotGain
       , SUM(CASE WHEN CC.ColorCharID = 10 THEN     [ColorCharsValue] END) As [Gray_L*]
       , SUM(CASE WHEN CC.ColorCharID = 13 THEN     [ColorCharsValue] END) As [G7NPDC]  
       , COUNT_BIG(*) AS CountBig 
FROM CPSync.Measurement 
INNER JOIN CPSync.MeasurementData ON  Measurement.MeasurementID = MeasurementData.MeasurementID
INNER JOIN CPSync.MeasuredColorChar As MC ON MC.MeasurementDataID = MeasurementData.MeasurementDataID
INNER JOIN CPSync.ColorChar AS CC ON MC.ColorCharsID =CC.ColorCharID
Group By MC.MeasurementDataID

Answer 1

更改

之类的行

SUM(CASE WHEN CC.ColorCharID = 11 THEN [ColorCharsValue] END ) AS [Gray_a*]

到

SUM(CASE WHEN CC.ColorCharID = 11 THEN [ColorCharsValue] ELSE 0 END ) AS [Gray_a*]

COUNT_BIG：if允许跟踪物化行。就像非unqiue聚集索引中的“uniquifier”一样。 COUNT_BIG允许大视图的32位溢出。

Answer 2

或者，您可以替换它：

SELECT MC.MeasurementDataID
   , SUM(CASE WHEN CC.ColorCharID = 11 THEN [ColorCharsValue] END ) AS [Gray_a*] 
   , SUM(CASE WHEN CC.ColorCharID = 12 THEN [ColorCharsValue] END) AS [Gray_b*]
   , SUM(CASE WHEN CC.ColorCharID = 4 THEN [ColorCharsValue] END) AS [ΔF]
   , SUM(CASE WHEN CC.ColorCharID = 9 THEN [ColorCharsValue] END) As DotGain
   , SUM(CASE WHEN CC.ColorCharID = 10 THEN     [ColorCharsValue] END) As [Gray_L*]
   , SUM(CASE WHEN CC.ColorCharID = 13 THEN     [ColorCharsValue] END) As [G7NPDC]  
   , COUNT_BIG(*) AS CountBig

使用这个更简单的代码：

SELECT MC.MeasurementDataID,
   , CC.ColorCharID
   , SUM([ColorCharsValue] ) AS [yourColumnName] 
   , COUNT_BIG(*) AS CountBig

并在您从索引视图中进行选择时将其展开

SQL Server无法创建索引视图

2 个答案: